The present invention relates to a method of reducing or scavenging hydrogen sulfide associated with or in a hydrocarbon stock. More particularly, the present invention relates to a method of reducing or scavenging hydrogen sulfide in a liquid hydrocarbon stock and/or gaseous hydrocarbon stock in admixture with hydrogen sulfide gas.
In the drilling, production, transport, storage, and processing of crude oil, including waste water associated with crude oil production, and in the storage of residual fuel oil, hydrogen sulfide which is a very toxic substance is often encountered. Also, at the oil well head, hydrogen sulfide-containing light hydrocarbon vapors are emitted and must be controlled. Uncontrolled emission of hydrogen sulfide gives rise to severe health hazards. Burning of such vapors neither solves the toxic gas problem nor is economical since the light hydrocarbons have significant value. Furthermore, hydrogen sulfide is often present in the underground water removed with the crude oil, in the crude oil itself and in the gases associated with such water and oil. When the water and oil are separated one from the other by the use of separation tanks, demulsification apparatus and the like, intolerable amounts of hydrogen sulfide are emitted as a gas which is associated with water and hydrocarbon vapors. Natural gases are often sour; that is they contain some hydrogen sulfides.
In accordance with the present invention, hydrocarbon liquids containing hydrogen sulfide, as well as hydrocarbon gases, such as natural gas or off gases from the production, transport, storage, and refining of crude oil can be controlled in a convenient and economical manner.